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Smoking-Cessation Advice to Patients With Chronic Obstructive Pulmonary Disease
Smoking-Cessation Advice to Patients With Chronic Obstructive Pulmonary Disease The Critical Roles of Health Insurance and Source of Care Timothy J. Tilert, BS, Jie Chen, PhD Introduction: Smoking cessation is the most effective therapeutic intervention for chronic obstructive pulmonary disease (COPD) patients. However, the proportion of smokers with COPD who have received physician advice to quit smoking is unknown. The purpose of this study is to assess the prevalence of receipt of smoking-cessation advice among adults with COPD and explore factors predicting advice receipt. Methods: This study employed nationally representative data from the Medical Expenditure Panel Survey (MEPS), collected in 2008–2011 on adults aged Z20 years. Logistic regression models were conducted to estimate the likelihood of receiving provider advice. Data were analyzed in 2014. Results: Four percent (95% CI¼3.8%, 4.2%) of adults reported being diagnosed with COPD. Among them, 38.5% (95% CI¼36.1%, 40.8%) were current smokers. Among those who had seen a physician in the past year, 85.6% (95% CI¼83.1%, 88.0%) were advised to quit smoking. Logistic regression revealed negative associations between receipt of smoking-cessation advice and having fewer healthcare visits (AOR¼0.41, 95% CI¼0.23, 0.72); being uninsured (AOR¼0.43, 95% CI¼0.22, 0.83); having no usual source of care (AOR¼0.39, 95% CI¼0.19, 0.80); and having no comorbid chronic diseases (AOR¼0.50, 95% CI¼0.29, 0.85).
Conclusions: Having no usual source of care and no health insurance are major barriers to receiving smoking-cessation advice among patients with COPD. The Patient Protection and Affordable Care Act has the potential to increase advice receipt in this high-risk population by expanding health insurance coverage and increasing the number of people with a usual source of care. (Am J Prev Med 2015;48(6):683–693) Published by Elsevier Inc. on behalf of American Journal of Preventive Medicine
Introduction
C
hronic obstructive pulmonary disease (COPD) affects 415 million Americans aged Z18 years.1–3 It is the third leading cause of death, both globally and in the U.S., claiming the lives of more than 138,000 Americans in 2010 alone.4,5 The economic burden of COPD on the healthcare system reached $32 billion in 2002, nearly 60% of which was attributable to direct costs.6 Given its enormous public health impact, Healthy People 2020 has established multiple From the Department of Behavioral and Community Health (Tilert), and Department of Health Services Administration (Chen), School of Public Health, University of Maryland, College Park, Maryland Address correspondence to: Timothy J. Tilert, BS, Department of Behavioral and Community Health, University of Maryland, School of Public Health, College Park MD 20740. E-mail: [email protected]. 0749-3797/$36.00 http://dx.doi.org/10.1016/j.amepre.2014.11.016
objectives specific to COPD, including “reduce deaths from chronic obstructive pulmonary disease among adults.”7 In spite of COPD sufferers having compromised lung function and respiratory symptoms, recent studies suggest that the rate of smoking is higher (33%–43%) among those with COPD than among the general population (18%).8–11 Though there is no known cure for COPD, quitting smoking has been shown to be a very costeffective12,13 and therapeutic intervention for smokers with COPD, with a number of studies linking cessation to a decrease in respiratory symptoms, reduction in rate of lung function decline, reduction in COPD exacerbations, and improved overall health status.14–18 Primary care providers can serve as trusted sources of cessation advice to their smoking COPD patients, particularly those who have regular sources of care and whose language and culture match those of their
Published by Elsevier Inc. on behalf of American Journal of Preventive Medicine
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providers. Provider advice alone has been shown to have a positive impact on cessation efforts among smoking patients. A recent analysis of National Health Interview Survey (NHIS) data showed that provider advice doubles the chances of success in self-reported smoking cessation among smoking patients in the general population.19 A meta-analysis comparing brief advice from physicians to no advice also showed that even brief advice provided by doctors to quit smoking could significantly increase the likelihood of successfully quitting smoking.20 Cokkinides et al.21 showed that the prevalence of receipt of advice to quit smoking from a healthcare provider for the U.S. adult smoking population increased from 52.9% in 2000 to 61.2% in 2005. The prevalence of advice to quit smoking from a healthcare provider among smokers with COPD, however, is unknown. Additionally, little is known of the factors predicting the receipt of cessation advice among smokers with COPD. Understanding both the prevalence and predictive factors of clinician advice to quit smoking among smokers with COPD could provide important evidence for costeffective interventions to reduce smoking rates among this high-risk population. In an effort to address these unknowns, the objectives of this study were to (1) assess the prevalence of clinician advice for smoking cessation among smokers with COPD in the U.S. and (2) explore predictive factors associated with the receipt of smokingcessation advice from a physician in this population.
Methods Study Sample This study consisted of analyses of Medical Expenditure Panel Survey (MEPS) 2008–2011 data, which were analyzed in 2014. The MEPS is a set of large-scale surveys of families and individuals, their medical providers, and employers across the U.S. and is sponsored by the Agency for Healthcare Research and Quality (AHRQ). The sampling design of the MEPS provides the ability to obtain nationally representative estimates of healthcare use, expenditures, sources of payment, and insurance coverage for the U.S. civilian non-institutionalized population. This research was not subject to review from the University of Maryland IRB, as it did not involve intervention or interaction with human subjects, collection of identifiable private data on living individuals, or data analysis of identifiable private information on living individuals. All data came from a publicly available source and were deidentified. A total of 131,032 individuals were surveyed for the 2008–2011 period. Among these participants, 83,934 (64.1% unweighted) were aged Z20 years and took part in the sample adult questionnaire, with 3,177 (3.8% unweighted) reporting ever being diagnosed with emphysema or being diagnosed with chronic bronchitis in the past year, that is, having COPD. This “ever emphysema/current chronic bronchitis” pairing has been used in a number of previous studies as a measure of self-reported
COPD.22,23 Among those classified as having COPD, 1,237 (38.9% unweighted) reported being a current smoker. Among these smokers with COPD, analyses were limited to those who had seen a physician in the past year and whose physician advice status could be ascertained. Excluding respondents with no doctor visits in the past 12 months (n=66) and respondents whose physician advice status could not be ascertained (n=69), the final analytic sample contained 1,102 people.
Measures The primary outcome of interest was the receipt of physician advice to quit smoking, taken directly from the MEPS survey question: Has a doctor advised you to quit smoking in the past 12 months? A dichotomous variable was constructed, which equaled 1 if the response was yes, and 0 if the response was no. Participants were defined as current smokers if they responded yes to a question asking them if they currently smoke. COPD was measured by a positive response to ever being diagnosed with emphysema or being diagnosed with chronic bronchitis in the past year. Independent variables included in our study were modeled after prior studies assessing the physician–patient relationship.24 Specifically, logistic regression models controlled for age (20–39, 40– 64, and Z65 years); gender; race and ethnicity (non-Hispanic whites, non-Hispanic African Americans, other non-Hispanics, and Hispanics); education (less than high school graduate and high school graduate or more); and urban or rural status of the residence. Two health needs indicators also were controlled for, including self-reported health status (very good or excellent and good, fair, or poor) and comorbid chronic disease diagnosis, a binary index of the presence of diabetes, cancer, asthma, chronic heart disease, high blood pressure, myocardial infarction, and other heart disease. Models additionally controlled for socioeconomic variables, including poverty status (o100% of the federal poverty level [FPL], between 100% and 200% of FPL, and 4200% of FPL); usual source of care; and insurance coverage status. Usual source of care was operationalized by assigning either the location of the usual source of care (doctor’s office, hospital, and non-hospital place) if the participant had a usual source of care or no usual source of care if the participant did not. Health insurance coverage was categorized into private health insurance (people having any private insurance coverage); public health insurance only (people with only public insurance coverage); and uninsured (people without health insurance). Finally, as it is likely that smoking patients who engage in more interactions with physicians subsequently have more opportunities to receive physician-provided smoking-cessation advice, a variable denoting the number of healthcare visits in the past year was constructed as a proxy for the number of patient–physician interactions. This healthcare visits variable was constructed by summing the total number of office-based visits, hospital outpatient visits, hospital emergency room visits, and inpatient hospital stays in the past year.
Statistical Analysis Statistical analyses were performed using Stata, version 13.1. Interview weights were used to account for differential probabilities of selection and the complex MEPS sample design and to www.ajpmonline.org
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Table 1. Distribution of Study Participants Aged 20 Years and Older: MEPS Sample Adult Questionnaire, 2008–2011 Descriptives of full 4-year sample (all participants aged Z20 years) Count
Unweighted percent
Weighted percent (95% CI)
83,934
100
100
Male
38,229
45.6
48.2 (47.8, 48.6)
Female
45,705
54.5
51.8 (51.4, 52.2)
20–39
32,268
38.4
36.6 (35.6, 37.6)
40–64
37,717
44.9
45.3 (44.6, 46.1)
Z65
13,949
16.6
18.1 (17.3, 18.9)
Non-Hispanic white
39,617
47.2
68.0 (66.1, 69.8)
Non-Hispanic black
15,786
18.8
11.3 (10.1, 12.6)
Other Non-Hispanic
7,661
9.1
6.8 (5.8, 7.7)
20,870
24.9
13.9 (12.4, 15.5)
Total Gender
Age
Race and ethnic origin
Hispanic Education Less than HS graduate
17,138
20.8
13.9 (13.3, 14.6)
HS graduate or more
65,386
79.2
84.9 (84.2, 85.7)
In metropolitan statistical area
71,897
85.7
84.3 (81.8, 86.7)
Not in metropolitan statistical area
12,037
14.3
15.7 (13.3, 18.2)
14,813
17.7
11.9 (11.2, 12.5)
100% to 200% of poverty line
18,703
22.3
17.7 (17.1, 18.3)
Above 200% of poverty line
50,418
60.1
70.4 (69.4, 71.4)
Very good or excellent
45,570
54.5
58.2 (57.4, 59.0)
Good, fair, or poor
38,061
45.5
41.5 (40.6, 42.3)
Any private
49,401
58.9
67.9 (66.8, 69.1)
Public only
17,301
20.6
16.8 (16.0, 17.6)
Uninsured
17,232
20.5
15.3 (14.4, 16.1)
22,643
27.3
23.1 (22.3, 24.0)
Urbanicity of residence
Poverty status Below poverty line
Self-reported health status
Health insurance coverage
Usual source of health care No usual source of care
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obtain prevalence estimates and their SEs that were representative of the noninstitutionalized U.S. population aged Z20 years. Prevalence estimates were obtained for COPD, smokers with COPD, and smokers with COPD who received advice to quit smoking from a physician in the past year. Chi-square tests were performed to examine the association between each of the covariates and the receipt of advice from a physician to quit smoking in the past year. A multivariable logistic regression model was developed for the outcome of receiving advice to quit smoking from a physician, controlling for the other covariates. AORs and 95% CIs were reported. Moderating effects were assessed by interacting gender, age, and race/ethnicity with each of the significant predictors of advice receipt in the final logistic regression model. All analyses were adjusted by the survey weights and results are nationally representative.
Results The overall prevalence rate of COPD was 4.0% (95% CI¼3.8%, 4.2%). COPD was progressively more prevalent with age, with those aged Z65 years having a higher prevalence (9.6%) than those aged 40–64 years (4.2%) (po0.001), who, in turn, had a higher prevalence than those aged 20–39 years (1.0%) (po0.001). COPD also was more prevalent among those with less than a high school education (8.4%) than high school graduates (3.3%) (po0.001); those who perceived their health as good, fair, or poor (7.4%) than those who perceived their health as very good or excellent (1.5%) (po0.001); those with public only health insurance coverage (9.6%) versus those with either any private health insurance (3.0%) (po0.001) or no health insurance (2.2%) (po0.001); and higher for those diagnosed with a comorbid chronic disease (7.1%) than for those not diagnosed with a comorbid chronic disease (1.1%) (po0.001). People with more than ten healthcare visits in the past year
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Table 1. Distribution of Study Participants Aged 20 Years and Older: MEPS Sample Adult Questionnaire, 2008–2011 (continued)
Overall, 85.6% (95% CI=83.1%, 88.0%) of the smokers with COPD received advice from a physician in Descriptives of full 4-year sample (all participants the past 12 months to quit smoking. aged Z20 years) Uninsured individuals received Unweighted Weighted percent lower rates of physician advice Count percent (95% CI) (72.0%) than those with any private insurance (88.0%) (p=0.003) or Doctor’s office 17,089 20.6 22.2 (21.1, 23.3) those with only public insurance Hospital 12,956 15.7 13.1 (12.3, 13.8) (86.2%) (p=0.008). Those without a Non-hospital place 30,124 36.4 40.5 (39.3, 41.7) usual source of health care received less physician advice to quit smokComorbid chronic disease ing (70.2%) than those whose usual Yes 39,360 46.9 48.3 (47.5, 49.0) source of care was a doctor’s office No 44,574 53.1 51.7 (51.0, 52.5) (90.6%) (po0.001) or a nonhospital place (86.6%) (p=0.002). Health care visits in past year Individuals not diagnosed with a Z10 14,756 17.6 20.9 (20.3, 21.5) comorbid chronic disease had sig4–9 18,752 22.3 24.1 (23.6, 24.6) nificantly lower rates of physician advice receipt (75.1%) than those r3 50,426 60.1 55.1 (54.3, 55.8) with at least one comorbid chronic HS, high school; MEPS, Medical Expenditure Panel Survey. disease (87.5%) (p=0.008). Rates of physician advice to quit smoking had a higher rate of COPD (8.5%) than those with four increased progressively with number of healthcare visits, to nine visits (5.0%) (po0.001), who, in turn, had a with 77.1% receiving advice among those with three or higher rate than those with three or fewer visits (1.9%) fewer visits compared to 86.8% (p=0.009) receiving (po0.001). advice among those with four to nine visits and 91.4% The overall prevalence rate of smoking among those (po0.001) receiving advice among those with more than diagnosed with COPD was 38.5% (95% CI¼36.1%, ten visits. Bivariate chi-square analyses (Table 3) revealed 40.8%). Smoking among those with COPD was less significant differences between those who received advice prevalent in the oldest age group, with individuals aged to quit smoking from a physician and those who did not Z65 years having a lower prevalence (23.8%) than both receive advice and the levels of a number of covariates, those aged 20–39 years (48.7%) (po0.001) and those including age (p¼0.049); race and ethnic origin aged 40–64 years (49.9%) (po0.001). Smoking rates also (p¼0.033); health insurance coverage (po0.001); usual were lower for Hispanics (26.2%) than for non-Hispanic source of health care (po0.001); whether one was whites (39.3%) (po0.001); non-Hispanic blacks (35.8%) diagnosed with comorbid chronic disease (po0.001); (p¼0.009); and other non-Hispanics (44.2%) (p¼0.003). and number of healthcare visits in the past year Uninsured people with COPD had higher smoking rates (po0.001). (54.5%) than those with any private insurance (35.6%) After controlling for the other covariates, logistic (po0.001) and those with only public insurance (38.7%) regression results (Table 4) showed significant associa(po0.001). Those without a usual source of health care tions between the likelihood of smokers with COPD to had higher rates of smoking (55.3%) than those whose receive advice to quit smoking from a physician and usual source of care was a doctor’s office (33.0%) number of healthcare visits in the past year, levels of (po0.001); hospital (34.8%) (po0.001); or nonhealth insurance coverage, usual source of health care, hospital place (39.6%) (po0.001). Smoking rates were and whether one was diagnosed with a comorbid chronic higher for those not diagnosed with a chronic condition disease. People with three or fewer healthcare visits in the (48.6%) versus those diagnosed with at least one chronic past year were 0.41 times (95% CI¼0.23, 0.72) as likely to condition (36.8%) (p¼0.001). Smoking rates also receive smoking-cessation advice as those who had ten or increased with decreasing number of healthcare visits, more health care visits. Uninsured individuals were 0.43 with 30.3% smoking among those with more than ten times (95% CI¼0.22, 0.83) as likely to receive smokingvisits compared with 39.1% with four to nine visits cessation advice as those with any private insur(po0.001) and 52.0% with three or fewer visits ance. Those without a usual source of health care were (po0.001).(Tables 1 and 2) 0.39 times (95% CI¼0.19, 0.80) as likely to receive www.ajpmonline.org
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Table 2. Prevalence Rates of COPD, Smoking, and Physician Advice to Quit Smoking
% with COPD
% smokers among those with COPD
% receiving advice from physician to quit smoking among smokers with COPDa
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
3,177
4.0 (3.8, 4.2)
1,237
38.5 (36.1, 40.8)
938
85.6 (83.1, 88.0)
Male
1,293
3.6 (3.3, 3.9)
556
42.7 (38.9, 46.6)
414
85.8 (82.1, 89.4)
Female
1,884
4.4 (4.0, 4.7)
681
35.2 (32.3, 38.1)
524
85.4 (81.9, 88.8)
20–39
333
1.0 (0.8, 1.2)
153
48.7 (41.0, 56.4)
94
78.3 (69.0, 87.5)
40–64
1,554
4.2 (3.9, 4.5)
779
49.9 (46.4, 53.3)
598
85.9 (82.7, 89.1)
Z65
1,290
9.6 (8.8, 10.4)
305
23.8 (20.4, 27.2)
246
87.4 (82.9, 91.9)
Non-Hispanic white
2,119
4.8 (4.4, 5.1)
885
39.3 (36.7, 41.8)
689
86.1 (83.4, 88.9)
Non-Hispanic black
558
3.1 (2.7, 3.4)
208
35.8 (31.0, 40.6)
161
88.9 (82.9, 95.0)
Other Non-Hispanic
169
2.8 (2.0, 3.6)
59
44.2 (34.2, 54.3)
34
73.8 (58.0, 89.5)
Hispanic
331
1.7 (1.4, 1.9)
85
26.2 (19.7, 32.7)
54
79.9 (65.0, 94.8)
Less than HS graduate
1,087
8.4 (7.6, 9.3)
497
46.7 (42.3, 51.0)
372
86.0 (81.5, 90.4)
HS graduate or more
2,047
3.3 (3.1, 3.5)
732
35.2 (32.5, 37.9)
559
85.3 (82.1, 88.5)
2,425
3.6 (3.3, 3.9)
919
37.2 (34.7, 39.8)
687
85.8 (83.0, 88.6)
752
6.2 (5.4, 7.0)
318
42.3 (36.2, 48.3)
251
84.9 (79.7, 90.1)
Below poverty line
831
6.3 (5.6, 7.1)
407
50.0 (45.1, 54.8)
305
84.1 (79.9, 88.3)
100%–200% of poverty line
867
5.6 (5.1, 6.2)
329
38.4 (34.3, 42.5)
255
85.4 (80.1, 90.7)
Above 200% of poverty line
1,479
3.2 (2.9, 3.4)
501
34.7 (31.6, 37.8)
378
86.4 (82.7, 90.1)
627
1.5 (1.3, 1.7)
207
32.5 (27.9, 37.2)
144
83.7 (76.9, 90.6)
2,516
7.4 (6.9, 7.9)
1,018
40.3 (37.6, 43.0)
784
85.9 (83.4, 88.4)
Any private
1,379
3.0 (2.8, 3.3)
485
35.6 (32.2, 39.0)
378
88.0 (84.6, 91.4)
Public only
1,473
9.6 (8.8, 10.4)
584
38.7 (35.3, 42.2)
466
86.2 (82.1, 90.2)
Uninsured
325
2.2 (1.9, 2.5)
168
54.5 (48.2, 60.7)
94
72.0 (62.3, 81.7)
Total Gender
Age
Race and ethnic origin
Education
Urbanicity of residence In metropolitan statistical area Not in metropolitan statistical area Poverty status
Self-reported health status Very good or excellent Good, fair, or poor Health insurance coverage
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Table 2. Prevalence Rates of COPD, Smoking, and Physician Advice to Quit Smoking (continued)
% with COPD
% smokers among those with COPD
% receiving advice from physician to quit smoking among smokers with COPDa
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
No usual source of care
331
1.6 (1.4, 1.9)
180
55.3 (48.2, 62.5)
77
70.2 (60.2, 80.2)
Doctor’s office
865
5.1 (4.6, 5.5)
291
33.0 (28.3, 37.8)
243
90.6 (86.5, 94.8)
Hospital
547
4.6 (4.0, 5.3)
192
34.8 (29.1, 40.4)
147
83.2 (75.0, 91.4)
1,405
4.6 (4.2, 5.0)
563
39.6 (35.7, 43.4)
464
86.6 (83.6, 89.6)
Yes
2,756
7.1 (6.7, 7.5)
1,045
36.8 (34.3, 39.3)
826
87.5 (85.0, 90.0)
No
421
1.1 (0.9, 1.2)
192
48.6 (42.0, 55.3)
112
75.1 (66.5, 83.8)
Z10
1,343
8.5 (7.9, 9.2)
425
30.3 (26.9, 33.7)
370
91.4 (88.2, 94.6)
4–9
957
5.0 (4.5, 5.4)
371
39.1 (35.4, 42.8)
303
86.8 (81.7, 91.9)
r3
877
1.9 (1.7, 2.0)
441
52.0 (47.5, 56.6)
265
77.1 (71.8, 82.3)
Usual source of health care
Non-hospital place Comorbid chronic disease
Health care visits in past year
Source: the Medical Expenditure Panel Survey 2008–2011; adults aged Z20 years. Note: Boldface indicates a significant difference between this level (e.g., Non-Hispanic white) and one or more of the other levels for this category (e.g., race and ethnic origin) from pairwise tests. a Of the 1,237 smokers with COPD, 66 participants did not see a physician in the past year and the physician advice status could not be ascertained for an additional 69 participants, leaving 1,102 participants with smoking-cessation advice information. Of these 1,102 participants, 938 received smoking-cessation advice and 164 did not. COPD, chronic obstructive pulmonary disease; HS, high school.
smoking-cessation advice from a healthcare provider as those whose usual source of care was a doctor’s office. Finally, people with no comorbid chronic diseases were 0.50 times (95% CI¼0.29, 0.85) as likely to receive smoking-cessation advice from a healthcare provider as those with one or more comorbid chronic diseases. Gender, age, and race/ethnicity did not moderate the relationships between any of these significant predictors and the outcome of advice receipt.
Discussion The overall rate of self-reported COPD in this study was found to be 4.0%, which is comparable to the 5.1% rate found by Akinbami and colleagues22 using 2007–2009 NHIS data. The rates of COPD increased progressively with age, which also mirrors the findings in a number of other studies utilizing different data sources.25–27 The overall rate of smoking among those with COPD was found to be 38.5%, which lies approximately in the middle of the range of 33%–43% prevalence of smoking found in a number of studies of people with COPD.8–10
The overall rate of receiving smoking-cessation advice from a physician was found to be 85.6% for smokers with COPD, which is considerably higher than the 53%–69% range recently found for smokers in the general population.21,28,29 In their study of smoking-cessation advice in California, Gilpin et al.30 suggested that physicians tend to treat such advice as a therapeutic rather than preventive intervention, which might explain the higher rate of advice among those with COPD when compared to the general population. Results from the logistic regression model showed that after controlling for the number of healthcare visits and other factors, people with no health insurance, no usual source of care, and without comorbid chronic conditions were less likely to receive advice to quit smoking from a physician. The reduced rates of advice for those lacking a usual source of care or health insurance may be a function of low-quality patient–provider relationships resulting from continually changing providers. A theory on continuity of care suggests that, in primary care, a primary care doctor with accumulating knowledge of the patient’s history, values, hopes, and fears will provide www.ajpmonline.org
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Table 3. Sample Characteristics of Smokers with COPD Receiving and Not Receiving Smoking-Cessation Advice Smokers with COPD receiving smoking-cessation advice
Total
Smokers with COPD not receiving smoking-cessation advice
n
Percent (unweighted)
n
Percent (unweighted)
938
100.0
164
100.0
Gender
By-group comparison Chi-square p -value
0.956
Male
414
44.1
72
43.9
Female
524
55.9
92
56.1
Age
0.049
20–39
94
10.0
27
16.5
40–64
598
63.8
99
60.4
Z65
246
26.2
38
23.2
Race and ethnic origin
0.033
Non-Hispanic white
689
73.5
113
68.9
Non-Hispanic black
161
17.2
24
14.6
Other Non-Hispanic
34
3.6
13
7.9
Hispanic
54
5.8
14
8.5
Education
0.448
Less than HS graduate
372
40.0
60
36.8
HS graduate or more
559
60.0
103
63.2
Urbanicity of residence
0.638
In metropolitan statistical area
687
73.2
123
75.0
Not in metropolitan statistical area
251
26.8
41
25.0
Poverty status
0.805
Below poverty line
305
32.5
57
34.8
100%–200% of poverty line
255
27.2
45
27.4
Above 200% of poverty line
378
40.3
62
37.8
Self-reported health status
0.711
Very good or excellent
144
15.5
27
16.7
Good, fair, or poor
784
84.5
135
83.3 o0.001
Health insurance coverage Any private
378
40.3
56
34.2
Public only
466
49.7
74
45.1
Uninsured
94
10.0
34
20.7 o0.001
Usual source of health care No usual source of care
77
8.3
34
20.9
Doctor's office
243
26.1
27
16.6
Hospital
147
15.8
30
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Table 3. Sample Characteristics of Smokers with COPD Receiving and Not Receiving Smoking-Cessation Advice (continued) Smokers with COPD receiving smoking-cessation advice
Non-hospital place
Smokers with COPD not receiving smoking-cessation advice
n
Percent (unweighted)
n
Percent (unweighted)
464
49.8
72
44.2
By-group comparison Chi-square p -value
o0.001
Comorbid chronic disease Yes
826
88.1
122
74.4
No
112
11.9
42
25.6 o0.001
Health care visits in past year Z10
370
39.5
37
22.6
4–9
303
32.3
47
28.7
r3
265
28.3
80
48.8
Note: Boldface indicates statistical significance (p-valueo0.05). COPD, chronic obstructive pulmonary disease; HS, high school.
better care than a similarly qualified doctor who lacks such knowledge.31,32 Under this theory, it is reasonable to assume that this better care might include timely behavioral advice, including advice to quit smoking for those with COPD. The higher rates of advice for those with comorbid conditions might be explained by a heightened perceived risk of continued smoking on the part of the physician for these COPD patients. Given that just 485% of adult smokers with COPD received advice from a physician to quit smoking, approximately 15% of this population did not receive physician cessation advice. Though relatively small, this proportion may be clinically relevant, as it translates to approximately 500,000 people who did not receive smoking-cessation advice from a physician and whose pulmonary conditions and quality of life may be unnecessarily deteriorating as a result.
Limitations There were a number of limitations in the study. The most notable limitation is the lack of quantification of smoking behavior. The analyses conducted here only assessed whether a person smoked or not. COPD rates and smoking-cessation advice rates, however, likely vary based on how much or how often a person smokes. Another limitation, given the cross-sectional survey design, is the inability to assess whether those individuals identified as non-smoking COPD patients stopped smoking prior to the survey as a result of previously received, physician-provided advice. The outcome of physician advice is self-reported, which may additionally cause some recall or measurement error. For example, it
is possible that a report of no advice may reflect a participant’s inability to recall receiving advice as opposed to the participant not receiving advice. The sample size of the study was also a limitation. As chronic bronchitis was not collected in the MEPS prior to 2008, self-reported COPD information was only available for survey years 2008–2011. Given the limited sample size and only a 15% prevalence of no advice (or 164 total “events”), both the number and levels of variables that could be included in the modeling were limited.
Conclusions The U.S. Preventive Services Task Force issued a formal recommendation in 2009 that clinicians ask all adults about their tobacco use and provide tobacco-cessation interventions for those who use tobacco products.33 This study found that 15% of smokers with COPD are not receiving this recommended advice, more often those with no comorbid chronic conditions, no usual source of care, and no health insurance. With a national advice policy already in place, one strategy to increase physician cessation advice may be to implement local policies supporting physician advice at the point of care. Specifically, if hospitals, community health centers, health insurance plans, and physician supervisors can vigorously promote and encourage the delivery of smokingcessation advice from their physicians to all smoking patients, not just those with comorbid chronic conditions, then many currently non-advised COPD patients might get the smoking-cessation advice they so desperately need. Having no usual source of care and no health insurance were also found to be major barriers to www.ajpmonline.org
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Table 4. Logistic Regression Results Predicting Receipt of Smoking-Cessation Advice from a Physician Smokers with COPD receiving smoking-cessation advice OR (95% CI)
p -value
ref
—
0.93 (0.58, 1.47)
0.746
ref
—
40–64
1.17 (0.65, 2.09)
0.601
20–39
0.95 (0.39, 2.30)
0.903
Non-Hispanic white
ref
—
Non-Hispanic black
1.37 (0.67, 2.81)
0.382
Other Non-Hispanic
0.50 (0.20, 1.21)
0.121
Hispanic
0.94 (0.27, 3.21)
0.915
ref
—
1.12 (0.68, 1.85)
0.652
ref
—
1.06 (0.66, 1.70)
0.805
Above 200% of poverty line
ref
—
100%–200% of poverty line
1.16 (0.65, 2.06)
0.615
Below poverty line
0.97 (0.53, 1.79)
0.926
ref
—
1.20 (0.70, 2.04)
0.502
Any private
ref
—
Public only
0.78 (0.40, 1.53)
0.469
Uninsured
0.43 (0.22, 0.83)
0.013
ref
—
Hospital
0.58 (0.26, 1.29)
0.183
Non-hospital place
0.73 (0.40, 1.32)
0.298
No usual source of care
0.39 (0.19, 0.80)
0.011
Gender Male Female Age (years) Z65
Race and ethnic origin
Education HS graduate or more Less than HS graduate Urbanicity of residence Not in metropolitan statistical area In metropolitan statistical area Poverty status
Self-reported health status Good, fair, or poor Very good or excellent Health insurance coverage
Usual source of health care Doctor’s office
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Table 4. Logistic Regression Results Predicting Receipt of Smoking-Cessation Advice from a Physician (continued) Smokers with COPD receiving smoking-cessation advice OR (95% CI)
p -value
Yes
ref
—
No
0.50 (0.29, 0.85)
0.011
410
ref
—
4–10
0.65 (0.35, 1.23)
0.184
r3
0.41 (0.23, 0.72)
0.002
Comorbid chronic disease
Health care visits in past year
Note: F-adjusted (for complex survey design) goodness-of-fit test statistic: F(9,187)¼11,217, po0.001. Boldface indicates statistical significance (p-valueso0.05). COPD, chronic obstructive pulmonary disease; HS, high school.
receiving smoking-cessation advice among smokers with COPD. The Patient Protection and Affordability Care Act is expected to increase both the number of people with insurance and the number of individuals with a usual source of care which, based on our modeling results, could increase the receipt of advice from physicians to quit smoking among this high-risk population. The research presented here was not funded or sponsored in any way. No financial disclosures were reported by the authors of this paper.
9.
10.
11.
12.
References 1. CDC. Chronic obstructive pulmonary disease among adults—United States. MMWR. 2012;61(46):938–943. 2. Lin K, Watkins B, Johnson T, Rodriguez JA, Barton MB. U.S. Preventive Services Task Force. Screening for chronic obstructive pulmonary disease using spirometry: summary of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med. 2008;148(7): 535–543. http://dx.doi.org/10.7326/0003-4819-148-7-200804010-00213. 3. Mannino DM, Buist AS. Global burden of COPD: risk factors, prevalence, and future trends. Lancet. 2007;370(9589):765–773. http://dx.doi.org/10.1016/S0140-6736(07)61380-4. 4. WHO. Top Ten Causes of Death. Fact sheet No. 310. Geneva: WHO, 2014. www.who.int/mediacentre/factsheets/fs310/en/index.html. 5. Murphy SL, Xu J, Kochanek KD. Deaths: Final data for 2010. Natl Vital Stat Rep. 2013;61(4):1–117. www.cdc.gov/nchs/data/nvsr/nvsr61/ nvsr61_04.pdf. 6. Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for the Diagnosis, Management and Prevention of COPD. 2011. www.goldcopd.org/uploads/users/files/GOLDReport_ April112011.pdf. 7. Healthy People 2020. Respiratory diseases. USDHHS. 2014. www. healthypeople.gov/2020/topicsobjectives2020/objectiveslist.aspx?topi cId=36. 8. Wedzicha JA, Calverley PM, Seemungal TA, Hagan G, Ansari Z, Stockley RA. INSPIRE Investigators. The prevention of chronic obstructive pulmonary disease exacerbations by salmeterol/fluticasone
13.
14.
15.
16.
17.
18.
19.
propionate or tiotropium bromide. Am J Respir Crit Care Med. 2008;177(1):19–26. http://dx.doi.org/10.1164/rccm.200707-973OC. Calverley PM, Anderson JA, Celli B, et al. TORCH investigators. Salmeterol and fluticasone propionate and survival in chronic obstructive pulmonary disease. N Engl J Med. 2007;356(8): 775–789. http://dx.doi.org/10.1056/NEJMoa063070. Hilberink SR, Jacobs JE, Bottema BJ. de Vries H, Grol RP. Smoking cessation in patients with COPD in daily general practice (SMOCC): six months’ results. Prev Med. 2005;41(5-6):822–827. http://dx.doi.org/ 10.1016/j.ypmed.2005.08.003. National Health Interview Survey (NHIS). Early release of selected estimates based on data from the 2013 National Health Interview Survey: current cigarette smoking. National Center for Health Statistics. 2014. www.cdc.gov/nchs/data/nhis/earlyrelease/earlyrelease201406_ 08.pdf. Buck DJ, Richmond RL, Mendelsohn CP. Cost-effectiveness analysis of a family physician delivered smoking cessation program. Prev Med. 2000;31(6):641–648. http://dx.doi.org/10.1006/pmed.2000.0756. Wouters EF. Economic analysis of the Confronting COPD survey: an overview of results. Respir Med. 2003;97(suppl C):S3–S14. http://dx.doi.org/10.1016/S0954-6111(03)80020-3. Stratelis G, Mölstad S, Jakobsson P, Zetterström O. The impact of repeated spirometry and smoking cessation advice on smokers with mild COPD. Scand J Prim Health Care. 2006;24(3):133–139. http://dx.doi.org/10.1080/02813430600819751. Bolliger CT, Zellweger JP, Danielsson T, et al. Influence of long-term smoking reduction on health risk markers and quality of life. Nicotine Tob Res. 2002;4(4):433–439. http://dx.doi.org/10.1080/1462220021000018380. Anthonisen NR, Connett JE, Murray RP. Smoking and lung function of Lung Health Study participants after 11 years. Am J Respir Crit Care Med. 2002;166(5):675–679. http://dx.doi.org/10.1164/rccm.2112096. Kanner RE, Connett JE, Williams DE, Buist AS. Effects of randomized assignment to a smoking cessation intervention and changes in smoking habits on respiratory symptoms in smokers with early chronic obstructive pulmonary disease: the Lung Health Study. Am J Med. 1999;106(4):410–416. http://dx.doi.org/10.1016/S0002-9343(99)000 56-X. Anthonisen NR, Connett JE, Kiley JP, et al. Effects of smoking intervention and the use of an inhaled anticholinergic bronchodilator on the rate of decline of FEV1: the Lung Health Study. JAMA. 1994; 272(19):1497–1505. http://dx.doi.org/10.1001/jama.1994.03520190043 033. Bao Y, Duan N, Fox SA. Is some provider advice on smoking cessation better than no advice? An instrumental variable analysis of the 2001
www.ajpmonline.org
Tilert and Chen / Am J Prev Med 2015;48(6):683–693
20.
21.
22.
23.
24.
25.
26.
National Health Interview Survey. Health Serv Res. 2006;41(6): 2114–2135. http://dx.doi.org/10.1111/j.1475-6773.2006.00592.x. Stead LF, Bergson G, Lancaster T. Physician advice for smoking cessation. Cochrane Database Syst Rev. 2008;2:CD000165. http://dx.doi.org/10.1002/14651858.CD000165.pub3. Cokkinides VE, Halpern MT, Barbeau EM, Ward E, Thun MJ. Racial and ethnic disparities in smoking-cessation interventions: analysis of the 2005 National Health Interview Survey. Am J Prev Med. 2008;34(5): 404–412. http://dx.doi.org/10.1016/j.amepre.2008.02.003. Akinbami LJ, Liu X. Chronic obstructive pulmonary disease among adults aged 18 and over in the United States, 1998–2009. NCHS data brief. 2011;63:1–8. Mannino DM, Homa DM, Akinbami L, Ford ES, Redd SC. Chronic obstructive pulmonary disease surveillance—United States, 1971– 2000. MMWR Surveill Summ. 2002;51(6):1–16. Vargas-Bustamante A, Chen J. Physicians cite hurdles ranging from lack of coverage to poor communication in providing high-quality care to Latinos. Health Aff (Millwood). 2011;30(10):1921–1929. http://dx.doi.org/10.1377/hlthaff.2011.0344. Menezes AM, Perez-Padilla R, Jardim JR, et al. PLATINO Team. Chronic obstructive pulmonary disease in five Latin American cities (the PLATINO study): a prevalence study. Lancet. 2005;366(9500): 1875–1881. http://dx.doi.org/10.1016/S0140-6736(05)67632-5. Tilert T, Dillon C, Paulose-Ram R, Hnizdo E, Doney B. Estimating the U.S. prevalence of chronic obstructive pulmonary disease using preand post-bronchodilator spirometry: The National Health and
June 2015
27.
28.
29.
30.
31. 32.
33.
693
Nutrition Examination Survey (NHANES) 2007-2010. Respir Res. 2013;14:103. http://dx.doi.org/10.1186/1465-9921-14-103. Vollmer WM, Gíslason T, Burney P, et al. Comparison of spirometry criteria for the diagnosis of COPD: results from the BOLD study. Eur Respir J. 2009;34(3):588–597. http://dx.doi.org/10.1183/09031936.00164608. Lopez-Quintero C, Crum RM, Neumark YD. Racial/ethnic disparities in report of physician-provided smoking cessation advice: analysis of the 2000 National Health Interview Survey. Am J Public Health. 2006;96(12):2235–2239. http://dx.doi.org/10.2105/AJPH.2005.071035. Houston TK, Scarinci IC, Person SD, Greene PG. Patient smoking cessation advice by health care providers: the role of ethnicity, socioeconomic status, and health. Am J Public Health. 2005;95(6): 1056–1061. http://dx.doi.org/10.2105/AJPH.2004.039909. Gilpin EA, Pierce JP, Johnson M, Bal D. Physician advice to quit smoking: results from the 1990 California Tobacco Survey. J Gen Intern Med. 1993;8(10):549–553. http://dx.doi.org/10.1007/BF02599637. Bass RD, Windle C. Continuity of care: an approach to measurement. Am J Psychiatry. 1972;129(2):196–201. Freeman G. Continuity of care in general practice: a review and critique. Fam Pract. 1984;1(4):245–252. http://dx.doi.org/10.1093/ fampra/1.4.245. U.S. Preventive Services Task Force (USPSTF). Counseling and interventions to prevent tobacco use and tobacco-caused disease in adults and pregnant women: U.S. Preventive Services Task Force reaffirmation recommendation statement. Ann Intern Med. 2009;150(8): 551–555. http://dx.doi.org/10.7326/0003-4819-150-8-200904210-00009.
Conclusions: Having no usual source of care and no health insurance are major barriers to receiving smoking-cessation advice among patients with COPD. The Patient Protection and Affordable Care Act has the potential to increase advice receipt in this high-risk population by expanding health insurance coverage and increasing the number of people with a usual source of care. (Am J Prev Med 2015;48(6):683–693) Published by Elsevier Inc. on behalf of American Journal of Preventive Medicine
Introduction
C
hronic obstructive pulmonary disease (COPD) affects 415 million Americans aged Z18 years.1–3 It is the third leading cause of death, both globally and in the U.S., claiming the lives of more than 138,000 Americans in 2010 alone.4,5 The economic burden of COPD on the healthcare system reached $32 billion in 2002, nearly 60% of which was attributable to direct costs.6 Given its enormous public health impact, Healthy People 2020 has established multiple From the Department of Behavioral and Community Health (Tilert), and Department of Health Services Administration (Chen), School of Public Health, University of Maryland, College Park, Maryland Address correspondence to: Timothy J. Tilert, BS, Department of Behavioral and Community Health, University of Maryland, School of Public Health, College Park MD 20740. E-mail: [email protected]. 0749-3797/$36.00 http://dx.doi.org/10.1016/j.amepre.2014.11.016
objectives specific to COPD, including “reduce deaths from chronic obstructive pulmonary disease among adults.”7 In spite of COPD sufferers having compromised lung function and respiratory symptoms, recent studies suggest that the rate of smoking is higher (33%–43%) among those with COPD than among the general population (18%).8–11 Though there is no known cure for COPD, quitting smoking has been shown to be a very costeffective12,13 and therapeutic intervention for smokers with COPD, with a number of studies linking cessation to a decrease in respiratory symptoms, reduction in rate of lung function decline, reduction in COPD exacerbations, and improved overall health status.14–18 Primary care providers can serve as trusted sources of cessation advice to their smoking COPD patients, particularly those who have regular sources of care and whose language and culture match those of their
Published by Elsevier Inc. on behalf of American Journal of Preventive Medicine
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providers. Provider advice alone has been shown to have a positive impact on cessation efforts among smoking patients. A recent analysis of National Health Interview Survey (NHIS) data showed that provider advice doubles the chances of success in self-reported smoking cessation among smoking patients in the general population.19 A meta-analysis comparing brief advice from physicians to no advice also showed that even brief advice provided by doctors to quit smoking could significantly increase the likelihood of successfully quitting smoking.20 Cokkinides et al.21 showed that the prevalence of receipt of advice to quit smoking from a healthcare provider for the U.S. adult smoking population increased from 52.9% in 2000 to 61.2% in 2005. The prevalence of advice to quit smoking from a healthcare provider among smokers with COPD, however, is unknown. Additionally, little is known of the factors predicting the receipt of cessation advice among smokers with COPD. Understanding both the prevalence and predictive factors of clinician advice to quit smoking among smokers with COPD could provide important evidence for costeffective interventions to reduce smoking rates among this high-risk population. In an effort to address these unknowns, the objectives of this study were to (1) assess the prevalence of clinician advice for smoking cessation among smokers with COPD in the U.S. and (2) explore predictive factors associated with the receipt of smokingcessation advice from a physician in this population.
Methods Study Sample This study consisted of analyses of Medical Expenditure Panel Survey (MEPS) 2008–2011 data, which were analyzed in 2014. The MEPS is a set of large-scale surveys of families and individuals, their medical providers, and employers across the U.S. and is sponsored by the Agency for Healthcare Research and Quality (AHRQ). The sampling design of the MEPS provides the ability to obtain nationally representative estimates of healthcare use, expenditures, sources of payment, and insurance coverage for the U.S. civilian non-institutionalized population. This research was not subject to review from the University of Maryland IRB, as it did not involve intervention or interaction with human subjects, collection of identifiable private data on living individuals, or data analysis of identifiable private information on living individuals. All data came from a publicly available source and were deidentified. A total of 131,032 individuals were surveyed for the 2008–2011 period. Among these participants, 83,934 (64.1% unweighted) were aged Z20 years and took part in the sample adult questionnaire, with 3,177 (3.8% unweighted) reporting ever being diagnosed with emphysema or being diagnosed with chronic bronchitis in the past year, that is, having COPD. This “ever emphysema/current chronic bronchitis” pairing has been used in a number of previous studies as a measure of self-reported
COPD.22,23 Among those classified as having COPD, 1,237 (38.9% unweighted) reported being a current smoker. Among these smokers with COPD, analyses were limited to those who had seen a physician in the past year and whose physician advice status could be ascertained. Excluding respondents with no doctor visits in the past 12 months (n=66) and respondents whose physician advice status could not be ascertained (n=69), the final analytic sample contained 1,102 people.
Measures The primary outcome of interest was the receipt of physician advice to quit smoking, taken directly from the MEPS survey question: Has a doctor advised you to quit smoking in the past 12 months? A dichotomous variable was constructed, which equaled 1 if the response was yes, and 0 if the response was no. Participants were defined as current smokers if they responded yes to a question asking them if they currently smoke. COPD was measured by a positive response to ever being diagnosed with emphysema or being diagnosed with chronic bronchitis in the past year. Independent variables included in our study were modeled after prior studies assessing the physician–patient relationship.24 Specifically, logistic regression models controlled for age (20–39, 40– 64, and Z65 years); gender; race and ethnicity (non-Hispanic whites, non-Hispanic African Americans, other non-Hispanics, and Hispanics); education (less than high school graduate and high school graduate or more); and urban or rural status of the residence. Two health needs indicators also were controlled for, including self-reported health status (very good or excellent and good, fair, or poor) and comorbid chronic disease diagnosis, a binary index of the presence of diabetes, cancer, asthma, chronic heart disease, high blood pressure, myocardial infarction, and other heart disease. Models additionally controlled for socioeconomic variables, including poverty status (o100% of the federal poverty level [FPL], between 100% and 200% of FPL, and 4200% of FPL); usual source of care; and insurance coverage status. Usual source of care was operationalized by assigning either the location of the usual source of care (doctor’s office, hospital, and non-hospital place) if the participant had a usual source of care or no usual source of care if the participant did not. Health insurance coverage was categorized into private health insurance (people having any private insurance coverage); public health insurance only (people with only public insurance coverage); and uninsured (people without health insurance). Finally, as it is likely that smoking patients who engage in more interactions with physicians subsequently have more opportunities to receive physician-provided smoking-cessation advice, a variable denoting the number of healthcare visits in the past year was constructed as a proxy for the number of patient–physician interactions. This healthcare visits variable was constructed by summing the total number of office-based visits, hospital outpatient visits, hospital emergency room visits, and inpatient hospital stays in the past year.
Statistical Analysis Statistical analyses were performed using Stata, version 13.1. Interview weights were used to account for differential probabilities of selection and the complex MEPS sample design and to www.ajpmonline.org
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Table 1. Distribution of Study Participants Aged 20 Years and Older: MEPS Sample Adult Questionnaire, 2008–2011 Descriptives of full 4-year sample (all participants aged Z20 years) Count
Unweighted percent
Weighted percent (95% CI)
83,934
100
100
Male
38,229
45.6
48.2 (47.8, 48.6)
Female
45,705
54.5
51.8 (51.4, 52.2)
20–39
32,268
38.4
36.6 (35.6, 37.6)
40–64
37,717
44.9
45.3 (44.6, 46.1)
Z65
13,949
16.6
18.1 (17.3, 18.9)
Non-Hispanic white
39,617
47.2
68.0 (66.1, 69.8)
Non-Hispanic black
15,786
18.8
11.3 (10.1, 12.6)
Other Non-Hispanic
7,661
9.1
6.8 (5.8, 7.7)
20,870
24.9
13.9 (12.4, 15.5)
Total Gender
Age
Race and ethnic origin
Hispanic Education Less than HS graduate
17,138
20.8
13.9 (13.3, 14.6)
HS graduate or more
65,386
79.2
84.9 (84.2, 85.7)
In metropolitan statistical area
71,897
85.7
84.3 (81.8, 86.7)
Not in metropolitan statistical area
12,037
14.3
15.7 (13.3, 18.2)
14,813
17.7
11.9 (11.2, 12.5)
100% to 200% of poverty line
18,703
22.3
17.7 (17.1, 18.3)
Above 200% of poverty line
50,418
60.1
70.4 (69.4, 71.4)
Very good or excellent
45,570
54.5
58.2 (57.4, 59.0)
Good, fair, or poor
38,061
45.5
41.5 (40.6, 42.3)
Any private
49,401
58.9
67.9 (66.8, 69.1)
Public only
17,301
20.6
16.8 (16.0, 17.6)
Uninsured
17,232
20.5
15.3 (14.4, 16.1)
22,643
27.3
23.1 (22.3, 24.0)
Urbanicity of residence
Poverty status Below poverty line
Self-reported health status
Health insurance coverage
Usual source of health care No usual source of care
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obtain prevalence estimates and their SEs that were representative of the noninstitutionalized U.S. population aged Z20 years. Prevalence estimates were obtained for COPD, smokers with COPD, and smokers with COPD who received advice to quit smoking from a physician in the past year. Chi-square tests were performed to examine the association between each of the covariates and the receipt of advice from a physician to quit smoking in the past year. A multivariable logistic regression model was developed for the outcome of receiving advice to quit smoking from a physician, controlling for the other covariates. AORs and 95% CIs were reported. Moderating effects were assessed by interacting gender, age, and race/ethnicity with each of the significant predictors of advice receipt in the final logistic regression model. All analyses were adjusted by the survey weights and results are nationally representative.
Results The overall prevalence rate of COPD was 4.0% (95% CI¼3.8%, 4.2%). COPD was progressively more prevalent with age, with those aged Z65 years having a higher prevalence (9.6%) than those aged 40–64 years (4.2%) (po0.001), who, in turn, had a higher prevalence than those aged 20–39 years (1.0%) (po0.001). COPD also was more prevalent among those with less than a high school education (8.4%) than high school graduates (3.3%) (po0.001); those who perceived their health as good, fair, or poor (7.4%) than those who perceived their health as very good or excellent (1.5%) (po0.001); those with public only health insurance coverage (9.6%) versus those with either any private health insurance (3.0%) (po0.001) or no health insurance (2.2%) (po0.001); and higher for those diagnosed with a comorbid chronic disease (7.1%) than for those not diagnosed with a comorbid chronic disease (1.1%) (po0.001). People with more than ten healthcare visits in the past year
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Table 1. Distribution of Study Participants Aged 20 Years and Older: MEPS Sample Adult Questionnaire, 2008–2011 (continued)
Overall, 85.6% (95% CI=83.1%, 88.0%) of the smokers with COPD received advice from a physician in Descriptives of full 4-year sample (all participants the past 12 months to quit smoking. aged Z20 years) Uninsured individuals received Unweighted Weighted percent lower rates of physician advice Count percent (95% CI) (72.0%) than those with any private insurance (88.0%) (p=0.003) or Doctor’s office 17,089 20.6 22.2 (21.1, 23.3) those with only public insurance Hospital 12,956 15.7 13.1 (12.3, 13.8) (86.2%) (p=0.008). Those without a Non-hospital place 30,124 36.4 40.5 (39.3, 41.7) usual source of health care received less physician advice to quit smokComorbid chronic disease ing (70.2%) than those whose usual Yes 39,360 46.9 48.3 (47.5, 49.0) source of care was a doctor’s office No 44,574 53.1 51.7 (51.0, 52.5) (90.6%) (po0.001) or a nonhospital place (86.6%) (p=0.002). Health care visits in past year Individuals not diagnosed with a Z10 14,756 17.6 20.9 (20.3, 21.5) comorbid chronic disease had sig4–9 18,752 22.3 24.1 (23.6, 24.6) nificantly lower rates of physician advice receipt (75.1%) than those r3 50,426 60.1 55.1 (54.3, 55.8) with at least one comorbid chronic HS, high school; MEPS, Medical Expenditure Panel Survey. disease (87.5%) (p=0.008). Rates of physician advice to quit smoking had a higher rate of COPD (8.5%) than those with four increased progressively with number of healthcare visits, to nine visits (5.0%) (po0.001), who, in turn, had a with 77.1% receiving advice among those with three or higher rate than those with three or fewer visits (1.9%) fewer visits compared to 86.8% (p=0.009) receiving (po0.001). advice among those with four to nine visits and 91.4% The overall prevalence rate of smoking among those (po0.001) receiving advice among those with more than diagnosed with COPD was 38.5% (95% CI¼36.1%, ten visits. Bivariate chi-square analyses (Table 3) revealed 40.8%). Smoking among those with COPD was less significant differences between those who received advice prevalent in the oldest age group, with individuals aged to quit smoking from a physician and those who did not Z65 years having a lower prevalence (23.8%) than both receive advice and the levels of a number of covariates, those aged 20–39 years (48.7%) (po0.001) and those including age (p¼0.049); race and ethnic origin aged 40–64 years (49.9%) (po0.001). Smoking rates also (p¼0.033); health insurance coverage (po0.001); usual were lower for Hispanics (26.2%) than for non-Hispanic source of health care (po0.001); whether one was whites (39.3%) (po0.001); non-Hispanic blacks (35.8%) diagnosed with comorbid chronic disease (po0.001); (p¼0.009); and other non-Hispanics (44.2%) (p¼0.003). and number of healthcare visits in the past year Uninsured people with COPD had higher smoking rates (po0.001). (54.5%) than those with any private insurance (35.6%) After controlling for the other covariates, logistic (po0.001) and those with only public insurance (38.7%) regression results (Table 4) showed significant associa(po0.001). Those without a usual source of health care tions between the likelihood of smokers with COPD to had higher rates of smoking (55.3%) than those whose receive advice to quit smoking from a physician and usual source of care was a doctor’s office (33.0%) number of healthcare visits in the past year, levels of (po0.001); hospital (34.8%) (po0.001); or nonhealth insurance coverage, usual source of health care, hospital place (39.6%) (po0.001). Smoking rates were and whether one was diagnosed with a comorbid chronic higher for those not diagnosed with a chronic condition disease. People with three or fewer healthcare visits in the (48.6%) versus those diagnosed with at least one chronic past year were 0.41 times (95% CI¼0.23, 0.72) as likely to condition (36.8%) (p¼0.001). Smoking rates also receive smoking-cessation advice as those who had ten or increased with decreasing number of healthcare visits, more health care visits. Uninsured individuals were 0.43 with 30.3% smoking among those with more than ten times (95% CI¼0.22, 0.83) as likely to receive smokingvisits compared with 39.1% with four to nine visits cessation advice as those with any private insur(po0.001) and 52.0% with three or fewer visits ance. Those without a usual source of health care were (po0.001).(Tables 1 and 2) 0.39 times (95% CI¼0.19, 0.80) as likely to receive www.ajpmonline.org
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Table 2. Prevalence Rates of COPD, Smoking, and Physician Advice to Quit Smoking
% with COPD
% smokers among those with COPD
% receiving advice from physician to quit smoking among smokers with COPDa
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
3,177
4.0 (3.8, 4.2)
1,237
38.5 (36.1, 40.8)
938
85.6 (83.1, 88.0)
Male
1,293
3.6 (3.3, 3.9)
556
42.7 (38.9, 46.6)
414
85.8 (82.1, 89.4)
Female
1,884
4.4 (4.0, 4.7)
681
35.2 (32.3, 38.1)
524
85.4 (81.9, 88.8)
20–39
333
1.0 (0.8, 1.2)
153
48.7 (41.0, 56.4)
94
78.3 (69.0, 87.5)
40–64
1,554
4.2 (3.9, 4.5)
779
49.9 (46.4, 53.3)
598
85.9 (82.7, 89.1)
Z65
1,290
9.6 (8.8, 10.4)
305
23.8 (20.4, 27.2)
246
87.4 (82.9, 91.9)
Non-Hispanic white
2,119
4.8 (4.4, 5.1)
885
39.3 (36.7, 41.8)
689
86.1 (83.4, 88.9)
Non-Hispanic black
558
3.1 (2.7, 3.4)
208
35.8 (31.0, 40.6)
161
88.9 (82.9, 95.0)
Other Non-Hispanic
169
2.8 (2.0, 3.6)
59
44.2 (34.2, 54.3)
34
73.8 (58.0, 89.5)
Hispanic
331
1.7 (1.4, 1.9)
85
26.2 (19.7, 32.7)
54
79.9 (65.0, 94.8)
Less than HS graduate
1,087
8.4 (7.6, 9.3)
497
46.7 (42.3, 51.0)
372
86.0 (81.5, 90.4)
HS graduate or more
2,047
3.3 (3.1, 3.5)
732
35.2 (32.5, 37.9)
559
85.3 (82.1, 88.5)
2,425
3.6 (3.3, 3.9)
919
37.2 (34.7, 39.8)
687
85.8 (83.0, 88.6)
752
6.2 (5.4, 7.0)
318
42.3 (36.2, 48.3)
251
84.9 (79.7, 90.1)
Below poverty line
831
6.3 (5.6, 7.1)
407
50.0 (45.1, 54.8)
305
84.1 (79.9, 88.3)
100%–200% of poverty line
867
5.6 (5.1, 6.2)
329
38.4 (34.3, 42.5)
255
85.4 (80.1, 90.7)
Above 200% of poverty line
1,479
3.2 (2.9, 3.4)
501
34.7 (31.6, 37.8)
378
86.4 (82.7, 90.1)
627
1.5 (1.3, 1.7)
207
32.5 (27.9, 37.2)
144
83.7 (76.9, 90.6)
2,516
7.4 (6.9, 7.9)
1,018
40.3 (37.6, 43.0)
784
85.9 (83.4, 88.4)
Any private
1,379
3.0 (2.8, 3.3)
485
35.6 (32.2, 39.0)
378
88.0 (84.6, 91.4)
Public only
1,473
9.6 (8.8, 10.4)
584
38.7 (35.3, 42.2)
466
86.2 (82.1, 90.2)
Uninsured
325
2.2 (1.9, 2.5)
168
54.5 (48.2, 60.7)
94
72.0 (62.3, 81.7)
Total Gender
Age
Race and ethnic origin
Education
Urbanicity of residence In metropolitan statistical area Not in metropolitan statistical area Poverty status
Self-reported health status Very good or excellent Good, fair, or poor Health insurance coverage
(continued on next page)
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688
Table 2. Prevalence Rates of COPD, Smoking, and Physician Advice to Quit Smoking (continued)
% with COPD
% smokers among those with COPD
% receiving advice from physician to quit smoking among smokers with COPDa
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
Count
Weighted percent (95% CI)
No usual source of care
331
1.6 (1.4, 1.9)
180
55.3 (48.2, 62.5)
77
70.2 (60.2, 80.2)
Doctor’s office
865
5.1 (4.6, 5.5)
291
33.0 (28.3, 37.8)
243
90.6 (86.5, 94.8)
Hospital
547
4.6 (4.0, 5.3)
192
34.8 (29.1, 40.4)
147
83.2 (75.0, 91.4)
1,405
4.6 (4.2, 5.0)
563
39.6 (35.7, 43.4)
464
86.6 (83.6, 89.6)
Yes
2,756
7.1 (6.7, 7.5)
1,045
36.8 (34.3, 39.3)
826
87.5 (85.0, 90.0)
No
421
1.1 (0.9, 1.2)
192
48.6 (42.0, 55.3)
112
75.1 (66.5, 83.8)
Z10
1,343
8.5 (7.9, 9.2)
425
30.3 (26.9, 33.7)
370
91.4 (88.2, 94.6)
4–9
957
5.0 (4.5, 5.4)
371
39.1 (35.4, 42.8)
303
86.8 (81.7, 91.9)
r3
877
1.9 (1.7, 2.0)
441
52.0 (47.5, 56.6)
265
77.1 (71.8, 82.3)
Usual source of health care
Non-hospital place Comorbid chronic disease
Health care visits in past year
Source: the Medical Expenditure Panel Survey 2008–2011; adults aged Z20 years. Note: Boldface indicates a significant difference between this level (e.g., Non-Hispanic white) and one or more of the other levels for this category (e.g., race and ethnic origin) from pairwise tests. a Of the 1,237 smokers with COPD, 66 participants did not see a physician in the past year and the physician advice status could not be ascertained for an additional 69 participants, leaving 1,102 participants with smoking-cessation advice information. Of these 1,102 participants, 938 received smoking-cessation advice and 164 did not. COPD, chronic obstructive pulmonary disease; HS, high school.
smoking-cessation advice from a healthcare provider as those whose usual source of care was a doctor’s office. Finally, people with no comorbid chronic diseases were 0.50 times (95% CI¼0.29, 0.85) as likely to receive smoking-cessation advice from a healthcare provider as those with one or more comorbid chronic diseases. Gender, age, and race/ethnicity did not moderate the relationships between any of these significant predictors and the outcome of advice receipt.
Discussion The overall rate of self-reported COPD in this study was found to be 4.0%, which is comparable to the 5.1% rate found by Akinbami and colleagues22 using 2007–2009 NHIS data. The rates of COPD increased progressively with age, which also mirrors the findings in a number of other studies utilizing different data sources.25–27 The overall rate of smoking among those with COPD was found to be 38.5%, which lies approximately in the middle of the range of 33%–43% prevalence of smoking found in a number of studies of people with COPD.8–10
The overall rate of receiving smoking-cessation advice from a physician was found to be 85.6% for smokers with COPD, which is considerably higher than the 53%–69% range recently found for smokers in the general population.21,28,29 In their study of smoking-cessation advice in California, Gilpin et al.30 suggested that physicians tend to treat such advice as a therapeutic rather than preventive intervention, which might explain the higher rate of advice among those with COPD when compared to the general population. Results from the logistic regression model showed that after controlling for the number of healthcare visits and other factors, people with no health insurance, no usual source of care, and without comorbid chronic conditions were less likely to receive advice to quit smoking from a physician. The reduced rates of advice for those lacking a usual source of care or health insurance may be a function of low-quality patient–provider relationships resulting from continually changing providers. A theory on continuity of care suggests that, in primary care, a primary care doctor with accumulating knowledge of the patient’s history, values, hopes, and fears will provide www.ajpmonline.org
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Table 3. Sample Characteristics of Smokers with COPD Receiving and Not Receiving Smoking-Cessation Advice Smokers with COPD receiving smoking-cessation advice
Total
Smokers with COPD not receiving smoking-cessation advice
n
Percent (unweighted)
n
Percent (unweighted)
938
100.0
164
100.0
Gender
By-group comparison Chi-square p -value
0.956
Male
414
44.1
72
43.9
Female
524
55.9
92
56.1
Age
0.049
20–39
94
10.0
27
16.5
40–64
598
63.8
99
60.4
Z65
246
26.2
38
23.2
Race and ethnic origin
0.033
Non-Hispanic white
689
73.5
113
68.9
Non-Hispanic black
161
17.2
24
14.6
Other Non-Hispanic
34
3.6
13
7.9
Hispanic
54
5.8
14
8.5
Education
0.448
Less than HS graduate
372
40.0
60
36.8
HS graduate or more
559
60.0
103
63.2
Urbanicity of residence
0.638
In metropolitan statistical area
687
73.2
123
75.0
Not in metropolitan statistical area
251
26.8
41
25.0
Poverty status
0.805
Below poverty line
305
32.5
57
34.8
100%–200% of poverty line
255
27.2
45
27.4
Above 200% of poverty line
378
40.3
62
37.8
Self-reported health status
0.711
Very good or excellent
144
15.5
27
16.7
Good, fair, or poor
784
84.5
135
83.3 o0.001
Health insurance coverage Any private
378
40.3
56
34.2
Public only
466
49.7
74
45.1
Uninsured
94
10.0
34
20.7 o0.001
Usual source of health care No usual source of care
77
8.3
34
20.9
Doctor's office
243
26.1
27
16.6
Hospital
147
15.8
30
18.4 (continued on next page)
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Table 3. Sample Characteristics of Smokers with COPD Receiving and Not Receiving Smoking-Cessation Advice (continued) Smokers with COPD receiving smoking-cessation advice
Non-hospital place
Smokers with COPD not receiving smoking-cessation advice
n
Percent (unweighted)
n
Percent (unweighted)
464
49.8
72
44.2
By-group comparison Chi-square p -value
o0.001
Comorbid chronic disease Yes
826
88.1
122
74.4
No
112
11.9
42
25.6 o0.001
Health care visits in past year Z10
370
39.5
37
22.6
4–9
303
32.3
47
28.7
r3
265
28.3
80
48.8
Note: Boldface indicates statistical significance (p-valueo0.05). COPD, chronic obstructive pulmonary disease; HS, high school.
better care than a similarly qualified doctor who lacks such knowledge.31,32 Under this theory, it is reasonable to assume that this better care might include timely behavioral advice, including advice to quit smoking for those with COPD. The higher rates of advice for those with comorbid conditions might be explained by a heightened perceived risk of continued smoking on the part of the physician for these COPD patients. Given that just 485% of adult smokers with COPD received advice from a physician to quit smoking, approximately 15% of this population did not receive physician cessation advice. Though relatively small, this proportion may be clinically relevant, as it translates to approximately 500,000 people who did not receive smoking-cessation advice from a physician and whose pulmonary conditions and quality of life may be unnecessarily deteriorating as a result.
Limitations There were a number of limitations in the study. The most notable limitation is the lack of quantification of smoking behavior. The analyses conducted here only assessed whether a person smoked or not. COPD rates and smoking-cessation advice rates, however, likely vary based on how much or how often a person smokes. Another limitation, given the cross-sectional survey design, is the inability to assess whether those individuals identified as non-smoking COPD patients stopped smoking prior to the survey as a result of previously received, physician-provided advice. The outcome of physician advice is self-reported, which may additionally cause some recall or measurement error. For example, it
is possible that a report of no advice may reflect a participant’s inability to recall receiving advice as opposed to the participant not receiving advice. The sample size of the study was also a limitation. As chronic bronchitis was not collected in the MEPS prior to 2008, self-reported COPD information was only available for survey years 2008–2011. Given the limited sample size and only a 15% prevalence of no advice (or 164 total “events”), both the number and levels of variables that could be included in the modeling were limited.
Conclusions The U.S. Preventive Services Task Force issued a formal recommendation in 2009 that clinicians ask all adults about their tobacco use and provide tobacco-cessation interventions for those who use tobacco products.33 This study found that 15% of smokers with COPD are not receiving this recommended advice, more often those with no comorbid chronic conditions, no usual source of care, and no health insurance. With a national advice policy already in place, one strategy to increase physician cessation advice may be to implement local policies supporting physician advice at the point of care. Specifically, if hospitals, community health centers, health insurance plans, and physician supervisors can vigorously promote and encourage the delivery of smokingcessation advice from their physicians to all smoking patients, not just those with comorbid chronic conditions, then many currently non-advised COPD patients might get the smoking-cessation advice they so desperately need. Having no usual source of care and no health insurance were also found to be major barriers to www.ajpmonline.org
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Table 4. Logistic Regression Results Predicting Receipt of Smoking-Cessation Advice from a Physician Smokers with COPD receiving smoking-cessation advice OR (95% CI)
p -value
ref
—
0.93 (0.58, 1.47)
0.746
ref
—
40–64
1.17 (0.65, 2.09)
0.601
20–39
0.95 (0.39, 2.30)
0.903
Non-Hispanic white
ref
—
Non-Hispanic black
1.37 (0.67, 2.81)
0.382
Other Non-Hispanic
0.50 (0.20, 1.21)
0.121
Hispanic
0.94 (0.27, 3.21)
0.915
ref
—
1.12 (0.68, 1.85)
0.652
ref
—
1.06 (0.66, 1.70)
0.805
Above 200% of poverty line
ref
—
100%–200% of poverty line
1.16 (0.65, 2.06)
0.615
Below poverty line
0.97 (0.53, 1.79)
0.926
ref
—
1.20 (0.70, 2.04)
0.502
Any private
ref
—
Public only
0.78 (0.40, 1.53)
0.469
Uninsured
0.43 (0.22, 0.83)
0.013
ref
—
Hospital
0.58 (0.26, 1.29)
0.183
Non-hospital place
0.73 (0.40, 1.32)
0.298
No usual source of care
0.39 (0.19, 0.80)
0.011
Gender Male Female Age (years) Z65
Race and ethnic origin
Education HS graduate or more Less than HS graduate Urbanicity of residence Not in metropolitan statistical area In metropolitan statistical area Poverty status
Self-reported health status Good, fair, or poor Very good or excellent Health insurance coverage
Usual source of health care Doctor’s office
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Table 4. Logistic Regression Results Predicting Receipt of Smoking-Cessation Advice from a Physician (continued) Smokers with COPD receiving smoking-cessation advice OR (95% CI)
p -value
Yes
ref
—
No
0.50 (0.29, 0.85)
0.011
410
ref
—
4–10
0.65 (0.35, 1.23)
0.184
r3
0.41 (0.23, 0.72)
0.002
Comorbid chronic disease
Health care visits in past year
Note: F-adjusted (for complex survey design) goodness-of-fit test statistic: F(9,187)¼11,217, po0.001. Boldface indicates statistical significance (p-valueso0.05). COPD, chronic obstructive pulmonary disease; HS, high school.
receiving smoking-cessation advice among smokers with COPD. The Patient Protection and Affordability Care Act is expected to increase both the number of people with insurance and the number of individuals with a usual source of care which, based on our modeling results, could increase the receipt of advice from physicians to quit smoking among this high-risk population. The research presented here was not funded or sponsored in any way. No financial disclosures were reported by the authors of this paper.
9.
10.
11.
12.
References 1. CDC. Chronic obstructive pulmonary disease among adults—United States. MMWR. 2012;61(46):938–943. 2. Lin K, Watkins B, Johnson T, Rodriguez JA, Barton MB. U.S. Preventive Services Task Force. Screening for chronic obstructive pulmonary disease using spirometry: summary of the evidence for the U.S. Preventive Services Task Force. Ann Intern Med. 2008;148(7): 535–543. http://dx.doi.org/10.7326/0003-4819-148-7-200804010-00213. 3. Mannino DM, Buist AS. Global burden of COPD: risk factors, prevalence, and future trends. Lancet. 2007;370(9589):765–773. http://dx.doi.org/10.1016/S0140-6736(07)61380-4. 4. WHO. Top Ten Causes of Death. Fact sheet No. 310. Geneva: WHO, 2014. www.who.int/mediacentre/factsheets/fs310/en/index.html. 5. Murphy SL, Xu J, Kochanek KD. Deaths: Final data for 2010. Natl Vital Stat Rep. 2013;61(4):1–117. www.cdc.gov/nchs/data/nvsr/nvsr61/ nvsr61_04.pdf. 6. Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for the Diagnosis, Management and Prevention of COPD. 2011. www.goldcopd.org/uploads/users/files/GOLDReport_ April112011.pdf. 7. Healthy People 2020. Respiratory diseases. USDHHS. 2014. www. healthypeople.gov/2020/topicsobjectives2020/objectiveslist.aspx?topi cId=36. 8. Wedzicha JA, Calverley PM, Seemungal TA, Hagan G, Ansari Z, Stockley RA. INSPIRE Investigators. The prevention of chronic obstructive pulmonary disease exacerbations by salmeterol/fluticasone
13.
14.
15.
16.
17.
18.
19.
propionate or tiotropium bromide. Am J Respir Crit Care Med. 2008;177(1):19–26. http://dx.doi.org/10.1164/rccm.200707-973OC. Calverley PM, Anderson JA, Celli B, et al. TORCH investigators. Salmeterol and fluticasone propionate and survival in chronic obstructive pulmonary disease. N Engl J Med. 2007;356(8): 775–789. http://dx.doi.org/10.1056/NEJMoa063070. Hilberink SR, Jacobs JE, Bottema BJ. de Vries H, Grol RP. Smoking cessation in patients with COPD in daily general practice (SMOCC): six months’ results. Prev Med. 2005;41(5-6):822–827. http://dx.doi.org/ 10.1016/j.ypmed.2005.08.003. National Health Interview Survey (NHIS). Early release of selected estimates based on data from the 2013 National Health Interview Survey: current cigarette smoking. National Center for Health Statistics. 2014. www.cdc.gov/nchs/data/nhis/earlyrelease/earlyrelease201406_ 08.pdf. Buck DJ, Richmond RL, Mendelsohn CP. Cost-effectiveness analysis of a family physician delivered smoking cessation program. Prev Med. 2000;31(6):641–648. http://dx.doi.org/10.1006/pmed.2000.0756. Wouters EF. Economic analysis of the Confronting COPD survey: an overview of results. Respir Med. 2003;97(suppl C):S3–S14. http://dx.doi.org/10.1016/S0954-6111(03)80020-3. Stratelis G, Mölstad S, Jakobsson P, Zetterström O. The impact of repeated spirometry and smoking cessation advice on smokers with mild COPD. Scand J Prim Health Care. 2006;24(3):133–139. http://dx.doi.org/10.1080/02813430600819751. Bolliger CT, Zellweger JP, Danielsson T, et al. Influence of long-term smoking reduction on health risk markers and quality of life. Nicotine Tob Res. 2002;4(4):433–439. http://dx.doi.org/10.1080/1462220021000018380. Anthonisen NR, Connett JE, Murray RP. Smoking and lung function of Lung Health Study participants after 11 years. Am J Respir Crit Care Med. 2002;166(5):675–679. http://dx.doi.org/10.1164/rccm.2112096. Kanner RE, Connett JE, Williams DE, Buist AS. Effects of randomized assignment to a smoking cessation intervention and changes in smoking habits on respiratory symptoms in smokers with early chronic obstructive pulmonary disease: the Lung Health Study. Am J Med. 1999;106(4):410–416. http://dx.doi.org/10.1016/S0002-9343(99)000 56-X. Anthonisen NR, Connett JE, Kiley JP, et al. Effects of smoking intervention and the use of an inhaled anticholinergic bronchodilator on the rate of decline of FEV1: the Lung Health Study. JAMA. 1994; 272(19):1497–1505. http://dx.doi.org/10.1001/jama.1994.03520190043 033. Bao Y, Duan N, Fox SA. Is some provider advice on smoking cessation better than no advice? An instrumental variable analysis of the 2001
www.ajpmonline.org
Tilert and Chen / Am J Prev Med 2015;48(6):683–693
20.
21.
22.
23.
24.
25.
26.
National Health Interview Survey. Health Serv Res. 2006;41(6): 2114–2135. http://dx.doi.org/10.1111/j.1475-6773.2006.00592.x. Stead LF, Bergson G, Lancaster T. Physician advice for smoking cessation. Cochrane Database Syst Rev. 2008;2:CD000165. http://dx.doi.org/10.1002/14651858.CD000165.pub3. Cokkinides VE, Halpern MT, Barbeau EM, Ward E, Thun MJ. Racial and ethnic disparities in smoking-cessation interventions: analysis of the 2005 National Health Interview Survey. Am J Prev Med. 2008;34(5): 404–412. http://dx.doi.org/10.1016/j.amepre.2008.02.003. Akinbami LJ, Liu X. Chronic obstructive pulmonary disease among adults aged 18 and over in the United States, 1998–2009. NCHS data brief. 2011;63:1–8. Mannino DM, Homa DM, Akinbami L, Ford ES, Redd SC. Chronic obstructive pulmonary disease surveillance—United States, 1971– 2000. MMWR Surveill Summ. 2002;51(6):1–16. Vargas-Bustamante A, Chen J. Physicians cite hurdles ranging from lack of coverage to poor communication in providing high-quality care to Latinos. Health Aff (Millwood). 2011;30(10):1921–1929. http://dx.doi.org/10.1377/hlthaff.2011.0344. Menezes AM, Perez-Padilla R, Jardim JR, et al. PLATINO Team. Chronic obstructive pulmonary disease in five Latin American cities (the PLATINO study): a prevalence study. Lancet. 2005;366(9500): 1875–1881. http://dx.doi.org/10.1016/S0140-6736(05)67632-5. Tilert T, Dillon C, Paulose-Ram R, Hnizdo E, Doney B. Estimating the U.S. prevalence of chronic obstructive pulmonary disease using preand post-bronchodilator spirometry: The National Health and
June 2015
27.
28.
29.
30.
31. 32.
33.
693
Nutrition Examination Survey (NHANES) 2007-2010. Respir Res. 2013;14:103. http://dx.doi.org/10.1186/1465-9921-14-103. Vollmer WM, Gíslason T, Burney P, et al. Comparison of spirometry criteria for the diagnosis of COPD: results from the BOLD study. Eur Respir J. 2009;34(3):588–597. http://dx.doi.org/10.1183/09031936.00164608. Lopez-Quintero C, Crum RM, Neumark YD. Racial/ethnic disparities in report of physician-provided smoking cessation advice: analysis of the 2000 National Health Interview Survey. Am J Public Health. 2006;96(12):2235–2239. http://dx.doi.org/10.2105/AJPH.2005.071035. Houston TK, Scarinci IC, Person SD, Greene PG. Patient smoking cessation advice by health care providers: the role of ethnicity, socioeconomic status, and health. Am J Public Health. 2005;95(6): 1056–1061. http://dx.doi.org/10.2105/AJPH.2004.039909. Gilpin EA, Pierce JP, Johnson M, Bal D. Physician advice to quit smoking: results from the 1990 California Tobacco Survey. J Gen Intern Med. 1993;8(10):549–553. http://dx.doi.org/10.1007/BF02599637. Bass RD, Windle C. Continuity of care: an approach to measurement. Am J Psychiatry. 1972;129(2):196–201. Freeman G. Continuity of care in general practice: a review and critique. Fam Pract. 1984;1(4):245–252. http://dx.doi.org/10.1093/ fampra/1.4.245. U.S. Preventive Services Task Force (USPSTF). Counseling and interventions to prevent tobacco use and tobacco-caused disease in adults and pregnant women: U.S. Preventive Services Task Force reaffirmation recommendation statement. Ann Intern Med. 2009;150(8): 551–555. http://dx.doi.org/10.7326/0003-4819-150-8-200904210-00009.